1. Technical Field
This invention relates to engineering surveying and data collection, and more particularly to a ruggedized hand held data collector capable of providing high precision, survey-grade GPS positioning, e.g., with accuracy to within 3 centimeters, while providing various alternate means of wireless communication.
2. Background Information
Throughout this application, various publications, patents and published patent applications are referred to by an identifying citation. The disclosures of the publications, patents and published patent applications referenced in this application are hereby incorporated by reference into the present disclosure.
High precision GPS (Global Positioning Satellite) receivers are commonly used in the surveying and construction industries. However, devices using these high precision GPS receivers have tended to be cumbersome and not well integrated for these industries. For example, users in these industries were required to carry a GPS receiver box in a backpack and move about a survey/construction site with a GPS antenna on a pole, and a data collector, with cables connecting the various components. Later, equipment manufacturers began to place the GPS receiver box on the pole, often mounted halfway up the pole below the antenna, sometimes integrated with the antenna. This was generally considered to be an improvement, but the pole tended to be top-heavy. Moreover, while hand-held GPS devices are available, such devices generally only provide low accuracy, e.g., 3-6 foot accuracy in real-time, while accuracy within about 3 cm or less is desired for surveying/construction applications. These conventional low precision devices also tend to be single purpose devices and/or consumer grade devices which are generally unsuitable for use in an engineering surveying environment where they are expected to be subjected to generally rough handling and potentially severe environmental conditions.
Users must typically carry additional devices, such as two-way radios, cell phones, and internet connectable devices for communication and data transfer. The need for multiple devices is often exacerbated by the different competing formats/protocols that are in use. For example, for positioning, both the GPS (Global Positioning Satellite) system operated by the U.S., and the GLONASS (Global Navigation Satellite System) operated by Russia, may be used, which typically requires mutually distinct receivers. Similarly, conventional point to point two-way radio may be needed for voice communication in areas lacking cellular coverage, while cellular communication may be used in other locales. Data transfer may require yet additional formats/protocols, including 802.11x and/or cellular/3G, etc., depending on the installed base of legacy equipment currently in use by a particular user/organization.
Thus, a need exists for a single device capable of addressing one or more of the aforementioned unresolved issues.